Guys, much because of the help from you all on here, I am basically ready to install! Please keep in mind I am a complete Linux Newbie (green!)

I have: Dell 1545 160GB HD, 2.16Ghz, 3GB RAM system, currently with Ubuntu(9.10) installed along with Vista via GRUB.

Planning to simply put Slackware into the Ubuntu partition (thereby deleting Ubuntu) and install LILO during Slack install.

Q: Will this delete GRUB and simply allow me to select Slack/Vista from LILO? (which would be ideal I suppose). The Slackware HOW-TO said that "Installing LILO can be dangerous. If you make a mistake it's possible to
make your hard drive unbootable. If you're new to Linux, it might be a
good idea to skip LILO installation and use the bootdisk to start your
system at first"

Should I worry about this?

Installing Lilo is normally not dangerous if you do it right but of course you should always back up important data. If Grub is installed in MBR and you install Lilo there Grub will be replaced. Personally I have always used MBR since my first installation (Slackware 3.6) and never had the slightest problem with that.

Thanks m95vebj! So,(remember im very much a newbie) I assume that GRUB/LILO usually default to the MBR(?), so that a default install of LILO should therefore wipeout/replace GRUB? (which is fine.)

The install dialog will ask you where you want to put the loader in a menu option. It's fairly obvious so you won't miss it.